A rotatable and retractable beauty instrument based on signal synchronization includes a main body. A back cover and a positioning head cover are respectively provided at rear and front sides of the main body. A synchronous rotating disk, a rise-fall retractable body and an active rubber body are sequentially arranged between the main body and the positioning head cover. A control main board is arranged between the main body and the back cover, and a direct-current speed-reducing motor is arranged on the control main board. A synchronous transmission circuit board is arranged on one surface of the synchronous rotating disk, and the rise-fall retractable body and multiple springs are arranged at a top of the other surface of the synchronous rotating disk. Based on the combination of the rise-fall retractable body and the synchronous rotating disk, the automatic extension and retraction is achieved.